Dielectric breakdown mechanism of thin-SiO2 studied by the post-breakdown resistance statistics

The dielectric breakdown mechanism of SiO₂ has been discussed on the basis of the experimental results of the post-breakdown resistance (R_bd) distribution. We have noticed for the first time that R_bd of SiO₂ in MOS devices is strongly related to the SiO₂ breakdown characteristics such as the polarity dependence or the oxide field dependence of Q_bd. In this paper, we discuss the dielectric breakdown mechanism of SiO₂ from the viewpoint of the statistical correlation between the R _bd distribution, the Q_bd. distribution, and the emission energy just at the SiO₂ breakdown, by changing the stress polarity, stress field, and the oxide thickness. For complete dielectric breakdown, it has been clarified that the R_bd distribution under the substrate electron injection is clearly different from that under the gate electron injection. We have also found that, irrespective of the stress current density, the gate oxide thickness and the stressing polarity, R_bd can be uniquely expressed by the energy dissipation at the occurrence of dielectric breakdown of SiO₂ for the complete breakdown. Furthermore, it has been clarified that R_bd does not depend on the energy dissipation at the occurrence of quasidielectric breakdown